i 23 
Steil. — Apogamy in Nep hr odium hirtipes , Hk. 
uniform thickness. The mother-cells grow considerably while the foregoing 
changes are taking place, although they vary much in size at any particular 
stage. Fig. 39, PI. VII, is drawn from a flattened spore mother-cell and 
hence appears unusually large. The details of chromosome formation were 
not followed. In diakinesis (Figs. 37 and 38, PI. VI, and Fig. 39. PI. VII) the 
chromosomes were counted, and there were found to be present at this time 
between sixty and sixty-five bivalent chromosomes. A multipolar spindle 
is formed which becomes bipolar (Figs. 40 and 41, PI. VII). The various 
stages in the division of the nuclei of the spore mother-cells were studied, and 
in the vast majority of cases the divisions are in every way normal (Figs. 42, 
43, 44, 45, 46, PI. VII). Sometimes anaphase figures were found in both the 
heterotypic and homotypic divisions with lagging chromosomes (Fig. 42, 
PI. VII). During the metaphase of the heterotypic division a few of the 
chromosomes pass to the poles while the remainder are still in the equatorial 
plate. Between the heterotypic and the homotypic divisions the individual 
chromosomes can be readily distinguished (Fig. 43, PI. VII). 
During the heterotypic division a granular zone appears in a broad 
equatorial plate midway between the daughter nuclei. This zone stains 
heavily and is composed of numerous small granules of cytoplasmic material 
(Figs. 43, 44, 45, and 46, PI. VII). In the homotypic division the axis of 
the spindles may be parallel (Fig. 45, PL VII), oblique (Fig. 46, PI. VII), or 
perpendicular to one another, or the axes of the two may lie in the same 
line. 
As a result of the division of the spore mother-cells thirty-two spores 
are produced, each having the reduced number of chromosomes, namely 
between sixty and sixty -five. Frequently the chromatin material in each 
member of the young tetrad is aggregated at one side of the nucleus and 
a clear region appears on the opposite side (Fig. 47, PI. VII). The cells in 
the preparation from which the figure was drawn showed no signs of 
plasmolysis, and since the same appearance was observed when different 
fixing fluids were used, this condition of the nucleus is not likely to have 
resulted from the technique employed. There is considerable growth in the 
size of the spores before the thick wall is formed about each one (Fig. 48, 
PI. VII). Sometimes chromatic material is found in the cytoplasm of the 
young spore (Fig. 54, PL VII). The origin of the nuclear material may be 
traced to chromosomes left in the cytoplasm during the division of the spore 
mother-cell nucleus. 
Since a number of sporogenous cells during the eight-celled stage were 
found in which the divisions were almost completed, it seemed probable, as 
I have already suggested, that at least in some cases such divisions may 
occur. A large number of preparations were examined, but no instance of 
such a division was found. The cells at different stages were also counted, 
and in only two cases observed did it appear that more than eight mother- 
